An end mill is mainly used when slot milling or counter boring is carried out.
JP 2005-125465 A discloses an end mill in which a step is provided on a rake surface of end cutting edge and peripheral cutting edge along the end cutting edge, and chip are pressed against the step and bent. It is also described in JP 2005-125465 A that a nick (recess) is formed in the end cutting edge.
JP 5-37411 Y also discloses that a nick (recess) is formed in an end cutting edge.